Elastic-fluid-turbine installation



Sept. 17, 1929. T. STEIN I ELASTIC. FLUID TURBINE INSTALLATION Filed Jan. 27, 1925 2 Sheets-Sheet Invefitof: Theodor Sfiein;

} His -Ator-neg.

Sept. 17, 1929. 'r. STEIN 1,

ELASTIC FLUID TURBINE INSTALLATION 2 Sheets-Sheet 2 Fi'lqd Jan. 27, 1925 Inventor: 24 22 Theodor" stein, f g His Attorney Patented Sept. 17, 1929 UNITED STATES PATENT OFFICE THEODOR STEIN, OF BERLIN-FRIEDENAU, GERMANY, ASSIGNOB, BY MESNE SIGN MEN'IS, '10 GENERAL ELECTRIC COMPANY, OF SGHENECTADY, NEW YORK, A. B-

POBATION OF NEW YORK ELASTIC-FLUID-TURBIN E INSTALLATION Application filed January 27, 1925, Serial No. 5,081, and in Germany February 5, 1924.

The present invention relates to elastic fluid turbine installations and especially installations wherein elastic fluid is extracted ke t constant or maintained at the desired va ue by some special means, there exists the difficulty that with changes in load on the turbine, or with changes in the initial or final pressures of the elastic fluid, there varies also the pressure of the stage from which elastic fluid is being extracted and hence the pressure of the elastic fluid supplied to the consumption agent. In many instances this is objectionable. For example in the case of an auxiliary turbine which is required to carry a substantially constant'load and which is supplied with'elastic fluid from an intermediate sta e of a main turbine, the condition exists t at when the pressure in the extraction stage decreases, the quantity of elastic fluid required to cover the power needs increases because of the lower pressure, and this increase may. become such as to render the operation uneconomical or even not possible at all. i

The difiiculty referred to aboveexists in especially aggravated form in the case of an auxiliary turbine or other elastic fluid consumption device wherein its requirement for elastic fluid is fairly constant and wherein the waste elastic fluid from it is used for the preheating of feed water. Consider, for example, the case of an installation comprising a main condensing turbine and an auxiliary turbine which has a substantially constant power requirement and which takes elastic fluid from an intermediate stage of the main .turbine, uti1izes a portion of its energy, and

then discharges it to afeed water heater, the auxiliary turbine being provided with a speed governor for maintaining the load on it. In such an installation with full load on the main turbine the pressure in the intermediate stage and hence the initial pressure for the auxiliary turbine is high and accordingly a small quantity of steam suifices to cover the power requirement. However, with part load on the main turbine, the intermediate pressure decreases, which means that the initial pressure of the elastic fluid su plied to the auxiliary turbines decreases so t at more elastic fluid is required to enable it to carry its load. This means that there is therefore available a larger amount of elastic fluid for preheating the feed water. At the same time, however, the quantity of feed water, i. e., the quantity of condensate from the main turbins to be preheated decreases so that while a greater quantit of elastic fluid is available for heating the eed water the condition actually exists that not a greater quantity but actually a lesser quantity of elastic fluid is required for the preheating. With -a still smaller load on the main turbine, the intermediate pressure may bedecreased below the pressure required for the preheatin so that the exhaust from the auxiliary tur ine must be dis osed of in some other manner rather than y heating the feed water. Or,

' if used for preheating the feed water, then a consideration of what I believe to be novel and my invention, attention is directed to the accompanying description and the claims appended thereto.

In the drawing, Fi .1 is a viewof a diagrammatic nature, il ustrating an embodiment of the invention; Fi 2 is a detail view showin a modification; ig. 3 is a view similarto I ig. 1 of a further modification, and Fig. 4 is a detail view of a part of the valve gear.

Referring to the drawing, 1 indicates a main condensing elastic fluid turbine provided with an admission conduit 2 and an exhaust conduit 3. It will be understood that the admission conduit will be providedv that the exhaust conduit 3 exhausts to a suitable condenser, not shown. Turbine 1 as illustrated may be taken as typical of any suit- Auxiliary elastic fluid turbine 4 is provided with several sets of admission nozzles throu h which elastic fluid is supplied to it. In t e present instance, there are six sets numbered 8, 9, 10, 11, 12 and 13. The flow of elastic fluid to these sets of nozzles is controlled b a series of valves 14, 15, 16, 17. 18 and 1 arranged in a valve chest 20. These valves are biased to closed positions by springs 21 and are adapted to be opened by cams 22 carried by a cam shaft 23. On the end of cam shaft 23 is a pinion 24 which engages a rack 25 on the upper end of a rod 26. The lower end of rod 26 is connected to the piston of an hydraulic motor 27. The pilot valve of hydraulic motor 27 is indicated at 28 and it has its stem 29 connected to the governor lever 30 and speed governor 31. Speed governor 31 is driven in any suitable manner from the shaft of turbine 4 and operates in response to the speed of turbine 4.

It will thus be seen that valves 14 to 19 inclusive are under the con rol of speed governor. 31 which serves to open and close them in accordance with the load on the auxiliary turbine. The speed governor and valve operating means is shown only diagrammatically and it will be taken as typical of any suitable means whereby valves 14 to 19 ma be successively opened and closed in accor ance with the speed of turbine 4. The arrangement shown is a known one, the connections providing a usual form of follow-up device.

Steam chest 20 is provided with partitions" dividing itinto three chambers 32, 33, 34. Chamber 32 contains valves 14 and 15, chamher 33 contains valves 16 and 17, and chamber 34 contains valves 18 and 19. Chamber 32 is connected by a conduit 35 to a point of intermediate pressure in turbine 1. Chamber 33 is connected by a conduit 36 to a point of.

intermediate pressure in turbine 1 higher than that at which conduit 35 is connected,

' and chamber 34 is connected by a conduit 37 to a source of high pressure elastic-fluid such return valve 38 which serves to prevent elastic fluid flowing through the conduit toward turbine 1.

With the above described arrangement when turbine 1 is operating at full load, the pressure of the elastic fluid in the stage to which conduit 35 is connected is sufliciently high so that when elastic fluid is supplied through it to turbine 4, it is sufficient to carry the load on turbine 4, and supply the required amount of elastic fluid for use in the feed water preheater. Under these circumstances, valve 14 or both valves 14 and 15 may be open, and the speed of the auxiliary turbine 4 will be regulated by speed governor 31 to maintain the required opening of these valves. Now, if the load on the main turbine 1 decreases, or for other reasons the intermediate pressure in turbine 1 decreases, then the pressure at the intermediate point of turbine 1 at which conduit 35 is connected may be decreased below that necessary to supply elastic fluid to operate turbine 4. When this takes place the speed governor 31 will operate to turn cam shaft 23 and eflect the openingof valve 16 or both valves 16 and 17 so as to supply elastic fluid to auxiliary turbine 4 through conduit 36. Since conduit 36 is connected to main turbine 1 at a point of higher pressure than that at which conduit 35 is connected, the auxiliary turbine 4 will now receive elastic fluid of a higher pressure with the result that it will be able tocarry its load. The arrangement is preferably such that when this occurs, the cams 22 controlling valves 14 and 15 will be moved to a position wherein valves 14 and 15 will be again closed.

However, such an arrangement need not necessarily be used because the required elastic fluid pressure supplied through conduit 36 will build up the pressure at the admission end of turbine 4 and for this reason limit the flow of elastic fluid through conduit 35. If now, the load on turbine 1 decreases still further, whereby the pressure at the point in turbine 1 at which conduit 36 is connected decreases to a value such that it is not sufliciently high to operate turbine 4, then the governor mechanism will operate to open either valve 18 or both valves 18 and .19, thereby admitting still higher pressure elastic fluid to auxiliary turbine 4. In this case, also, the arrangement may be such that when valves 18 and 19 are open, valves '16 and 17 will be closed or the arrangement may be such that they will remain open. A V

Thus it will be seen that with the abovedescribed construction, the auxiliary elastic fluid turbine 4 will be supplied always with elastic fluid of a pressure sufliciently high so that an excessive quantity of elastic fluid will not be required to operate it. As a result, the auxiliary turbine will always carry its load and in no case will it deliver an excessive quantity heater.

When circumstances justify it, valve 7 may be opened to convey a part or all the elastic fluid from exhaust conduit to a lowerpressure stage of main turbine 1. p

e valve gear for auxiliary turbine- 4, instead of being controlled by a speed governor, may be controlled by a governor of any other suitable type and responding to any other operating condition of the auxiliary turbine or other elastic fluid consumption agent. In Fig. 2 an arran ement wherein the valve ear is controlled by the pressure of the ex aust elastic fluid from the auxiliary turbine is illustrate In Fig. 2 pilot valve stem 29 of the hydraulic motor 27 is connected to a pressure responsive device of any suitable type. For example, a known type of diaphragm pressure responsive device may be used. The pressure responsive device is in turn connected by a pipe 41 to the exhaust conduit 5. By this arrangement the cam shaft 23 for operating of elastic fluid to the feed water prethe valve gear will be actuated in accordance with the pressure in conduit 5. In a similar manner a device responsive to some other operating condition of the turbine may be used if found desirable.

In Fig. 3 is illustrated a further modification of the invention wherein the valve gear 42 for the auxiliary elastic fluid turbine 4 comprises an elastic fluid chest or header 43 connected by of turbine 4. The flow of elastic fluid to header 43 is controlled by a series of valves 46, 47, 48 and 49 which in turn control the flow of elastic fluid through conduits 50, 51, and 52 leadin to points of different pressures in main tur ine 1, and a conduit 53 leadin to supply conduit 2 for main turbine 1. 0t erwise the arrangement shown in Fig. 3 is substantially the same as that shown in Fig. 1 and operates in the same manner.

As the pressure through the main turbine 1 varies, valves 46 to 49 inclusive will be successivel opened to admit elastic fluid of high; er and igher pressures to header 43, from lvvhenlee it-is supplied to the auxiliary turine In accordance with the revisions of the patent statutes, I have described the rinci le of operation of my invention, toget er with the apparatus whlch I now consider to re resent the best embodiment thereof, but I e- ;ire to have it understood that the apparatus IS shown is only illustrative and that the invention may be carried out b other means.

What I claim as new an desire to secure )y Letters Patent of the United States, is:--

1. In a power installation, the combinaion of a main turbine, an auxilia turbine,

t plurality of conduits connecting tile admision end of the auxiliary turbine to points if difi'erent pressures in the main turbine,

a conduit 44 to the nozzles valve means in each of said conduits, and means controlled by an 0 rating condition of the auxiliary turbine filiregulating said valve means.

2. In a power installation, the combination of a main turbine, an auxiliary turbine, a plurality of conduits connecting the admission end of the auxiliary turbine to points of different ressures in the main turbine, valve means in each of said conduits, and a speed governor driven b the auxiliary turbine for regulating said va ve means.

3. In a power installation, the combination of a main turbine, an auxiliary turbine, a plurality of conduits connecting the admission end of the auxiliary turbine to points of diflerent pressures in themain turbine, and an additional conduit connectin the admission end of the auxiliary turbme to a source of hi h pressure elastic fluid, valve means in eac controlled by an operating condition of the auxiliary turbine for successively opening the valve means in said first named conduits and finally opening the valve means in said additiona conduit.

In witness whereof, I have hereunto set my hand this 8th day of Janua 1925.

THEO R STEIN.

of said conduits, and means 

